The answer to that question will depend on the recipe you are using, and what kind (room temperarure or cold fermentation) and duration of fermentation you plan to use. If you can post it, that might help. Alternatively, if you know the style of pizza you want to make (e.g., New York, American, Neapolitan, etc.), maybe we can suggest a quantity to use. If you are using a recipe that calls for dry yeast, the conversion of the dry yeast to fresh yeast is an easy problem to solve (we will need to know whether the dry yeast is IDY or ADY).

I want to make Napoletan Style and I want to use the cold fermentation.Do you know the amount of fresh yeast for 25kg of flour ?

ronchonou,

To answer that question we need to know the duration of the cold fermentation. You might also tell us the hydration you plan to use and the amount of salt you plan to use. All of these factors are interrelated.

I'd like to be as helpful to you as I can inasmuch I don't want you to waste 25kg of flour if what I tell you does not work. But, to be honest, 8-12 hours of cold fermentation is not much, especially if you go directly from the forming of the dough balls (I am assuming you are not using an 8-12 hour bulk rise) to the refrigerator without any time spent resting at room temperature. Are you now using your dough recipe with dry yeast and are only interested in converting to fresh yeast, or is this a first-time try? If it is a first-time try, can you tell me what kind of rise you are looking for during the fermentation? Is it a rise of one-quarter, fifty percent or a hundred percent (a doubling)?

I also think that your salt level is too high for a cold fermented dough. High salt levels are often used for room temperature fermented Neapolitan style doughs but that doesn't necessarily mean that one should use the same levels for cold fermented versions. The role of salt in room temperature fermented doughs is quite different than for cold fermented doughs. If you are fixed on 2.8%, that will mean having to use even more yeast to compensate for the regulatory effect that high salt levels have on the fermentation process.

Once I have a clearer picture of what you are trying to achieve, I will try to answer your questions as best I can. If there other members who have been where you want to go, of course they should feel free to help you.

I won't use 25kg of flour it's just to have an idea.In a few months/year I want to open a restaurant.I want to make the dough the morning, directly make the balls of dough, let them at a cold fermentation.

How long will I have to let them in cold fermentation to have a napoletan result ?In your opinion, what the amount of salt and fresh yeast will I have to use ?

Traditionally, the practice in Naples has been to use room temperature fermentation of the dough. However, I understand that more recently there are some Neapolitan pizza operators who have been making cold fermented doughs. In the U.S., both methods are used. At one point in time, I would have guessed that cold fermentation was the more common and popular method, but there seems to have been a move in the past few years to making a more authentic Neapolitan style dough that is based on using room temperature (or a controlled temperature) fermentation.

If you are certain that you want to use the cold fermentation method for the Neapolitan style, I'd like to suggest that you read the following threads:

The second thread mentioned above relates to the first thread and describes a cold fermented Neapolitan style dough that one of our members, Mo, came up with in anticipating starting his own pizzeria. Judging from the website of his pizzeria at http://www.vesuvius-wfp.com/Vesuvius_Wood-Fired_Pizza/Promise.html, it looks like Mo is still in business, although I do not know exactly what recipe and flour he is now using.

There are some more recent threads and posts on cold fermented Neapolitan style doughs on the forum but I do not follow them as closely as I used to since I do not have a wood fired oven to benefit from that style. Maybe some of the members of the forum reading this thread may be able to offer you guidance on how to proceed.

Once you have considered the above material and you have a better idea as to how you think you would like to proceed, perhaps you can come back to the forum and we may be able to offer your specific advice or answers to your questions.

If I want to be more "authentic" and give up with the cold fermentation and make a fermentation at room temp, what is the exact process to make a good napoleatan pizzas ?I know that you have excellent results.

1-What the % of ingredients that you use (Is it possible to have the % of yeast for fresh yeast ?)2-The way to knead well (robot or by hand)3-The time of bulk rise4-The time with the dough balled5-In the case if I make 120 balls of dough and I sell only 60, what will I have to do with the 60 balls non-selled ?6-Is it possible to have a napoleatan result (or to have approximatively the same result) with an electric oven (It's diffucult in France to find an oven with wood)

Ronchonou;For a shop operation I would suggest the following dough formulation:Flour: 12 to 13% protein content (General Mills Harvest Kin or Superlative) 100%Salt: 1.75%Compressed Yeast: 1%Oil: 1%Water: (65F) 60%Procedure: Put water in mixing bowl, add salt, then flour and yeast. Mix 2-minutes at low speed, add the oil and mix 1 more minute at low speed. Finish mixing at medium speed for about 8-minutes, or first speed for 12-minutes. Target finished dough temperature is 80 to 85F. Take dough directly to the bench for scaling and balling. Place dough balls into plastic dough boxes and wipe the top of the dough balls with salad oil. Cross stack in the cooler for 2-hours, then down stack and nest the dough boxes. The dough will be ready to begin using after about 18-hours in the cooler. The unused dough can be held in the cooler for up to 3-days, but is at it's best on the second day. To use the dough, remove a quantity from the cooler and allow to temper AT room temperature for 2 to 2.5-hours, then begin opening the dough balls into skins for immediate use. The dough will remain good to use for 3-hours after you begin open the balls into skins. Any unused dough balls can be opened and placed onto screens and placed on a wire tree rack in the cooler (uncovered for 30-minutes) then cover with a rack cover or plastic bag. Use these pre-opened dough skins as soon as possible. To use the pre-opened skins, bring the rack out of the cooler and allow to temper AT room temperature for 30-minutes, remove the skin from the screen and resize, place onto peel with a little peel dust and dress to the order, then bake as normal Using this method you should never need to toss out any dough balls, and you will have a consistent product over the life of the dough balls.The amount of compressed yeast to use for 25Kg. of flour is 1% in this application, that calculates out to 250-grams.Tom Lehmann/The Dough Doctor

If you are really interested in making authentic Neapolitan dough as is made in Naples, I think you really need to use a 00 flour and a very-high temperature oven such as a wood-fired oven. In my opinion, the two go together. Also, with a room temperature fermentation, you will have to learn how to adjust the preparation of the dough to the changes in room temperature throughout the year. That takes skill and time to learn. You will also have to learn how to develop your inventory of dough balls so that you don't end up with more dough balls than you can use on any given day, although I understand that there are some Neapolitan pizza makers who do store unused dough balls in a cooler for use the next day. I think you can now see why some pizza operators prefer to use cold fermentation of their dough balls. What Tom Lehmann suggested is along the lines of a cold fermented dough although I doubt that you have the particular brands of flour that he mentioned. Can you tell us what kind of flours you have available to you where you are in France?

In France we can find easily Caputo 00 Flour.It's true that cold fermentation allows to keep the dough balled until 48h, that's why I was thinking of the method. In a restaurant, we don't know in advance the quantity that will be selled.The great question for me is the % of fresh yeast and salt with cold fermentation to have a pizza which inflate good in the oven.There are some electric oven that could have high level of temperature.For example, this oven can go until 400°C (752°F)http://www.restoconcept.com/Four_a_pizza_electrique_Tornati_forni.aspx

In France we can find easily Caputo 00 Flour.It's true that cold fermentation allows to keep the dough balled until 48h, that's why I was thinking of the method. In a restaurant, we don't know in advance the quantity that will be selled.The great question for me is the % of fresh yeast and salt with cold fermentation to have a pizza which inflate good in the oven.There are some electric oven that could have high level of temperature.For example, this oven can go until 400°C (752°F)http://www.restoconcept.com/Four_a_pizza_electrique_Tornati_forni.aspx

Thank you

ron, i recently made a pie that was 1.5 hours from mixing, to table. it used a blend of CY and IDY

sugar, yeasts, and water. bloom them for 5minstir salt and flour together, drizzle oil on top before adding the water, and stir flour togetheradd the water, stir with a wooden spoon, folding the outside inwards (see thread: lazy mans bread)bulk rise once until double or so, divide down. at this point, you can pan it for a pan pizza and let rise again(with an oiled pan) or ball with stretch and fold, and let rise again for a hand-tossed. sauce top and bake as needed. it had enough gluten formed that it came out fine for a pan pizza, but will need the additional rise and rest for a stretched pizza.

The great question for me is the % of fresh yeast and salt with cold fermentation to have a pizza which inflate good in the oven.

ronchonou,

I would say around 1% fresh yeast, as Tom mentioned. That would be for two or three days of cold fermentation. With a few experiments, you should be able to tell whether you need more or less. For the salt, I would start with 1.75%. Many people prefer more, sometimes up to 2.3% or more. Again, with a few experiments, you should be able to tell whether you should use more or less salt. For a cold fermented dough, the salt is more for taste rather than controlling the fermentation process as it would be if you were using a room temperature fermented dough.